Coalbed methane (CBM) resources in China are abundant, but the geological and engineering conditions are complex. The applicability of natural gas well drainage technology in coalbed methane wells is limited, especially for deep coalbed methane (coalbed methane resources buried deeper than 1000 m). Its drainage characteristics There are significant differences from shallow coalbed methane. Through theoretical analysis and on-site summary, this article systematically analyzes the characteristics of deep coalbed methane reservoirs, drainage stages and main control factors, and the development direction of drainage technology. The results show: ① Characteristics of deep coalbed methane: It generally has reservoir characteristics such as high reservoir pressure and temperature, sufficient formation energy, thick coal seams, high gas content, and abundant free gas. It also has characteristics such as low matrix permeability, poor pore connectivity, high effective stress, and low fracturing fluid return rate. ② Main control factors of drainage and production: In the early stage of drainage and pressure reduction, the influence of pulverized coal Drainage effect; in the stage from gas breakthrough to stable production, stress sensitivity is significant, and the number of shut-ins should be reduced to avoid formation pollution caused by discontinuous drainage; ③In terms of production stage division and drainage and production system: It is recommended that deep coalbed methane wells adopt a refined and quantitative five-stage or six-stage stage division, which is conducive to controlling the steady decline of bottom hole pressure. The purpose of the drainage and production system is to extend the stable production period. The duration of the stable production stage determines the final production capacity; ④ Development direction of drainage and production technology: integrated drainage and extraction throughout the life cycle of the gas well , geological engineering integrated drainage and mining machine learning and smart drainage and other technology applications. This research can provide certain guidance for the optimization of related process technologies for deep coalbed methane well drainage.

In order to solve the problem that the over-mass of the drilling arm affects the maneuverability and working stability, the drilling arm of JMZ type airborne anchor drill is studied, and the response surface method is used to optimize the structure. With the size parameter of the drill arm as the design variable, strength and stiffness as the constraint condition, and mass as the optimization objective, the response surface model was established by using the central combination design method, and the influence law of each variable on the maximum equivalent stress, maximum deformation and mass of the drill arm was analyzed. The response surface model was optimized and solved by using the multi-island genetic algorithm, and the optimal parameter combination was obtained. The results show that the cross section size of the inner cylinder of the fixed arm has the greatest influence on the maximum equivalent stress of the drilling arm, and the cross section size of the inner cylinder of the telescopic arm has the greatest influence on the maximum deformation and quality of the drilling arm. After optimization, the strength and stiffness of the drilling arm meet the requirements, the mass of the drilling arm is reduced by 7.83%, and the maximum equivalent stress is reduced by 14.58%.